1. Euclidean quantum mechanics: Analytical approach;Albeverio;Ann. Inst. Henri Poincare Phys. Theor.,1989
2. Mathematical Analysis;Apostol,1974
3. Bounds for the fundamental solution of a parabolic equation;Aronson;Bull. Amer. Math. Soc.,1967
4. Non-negative solutions of linear parabolic equations;Aronson;Ann. Sc. Norm. Super. Pisa Cl. Sci. (5),1968
5. S. Bernstein, Sur les liaisons entre les grandeurs aléatoires, in: Verhandlungen des Internationalen Mathematikerkongress, vol. 1, 1932, pp. 288–309.